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Although green coke contains polycyclic aromatics, their total concentration of about 250 mg/kg is below the critical level of 1000 mg/kg. Also the content of the key component benzopyrene (c. 25 mg/kg) is not critical. Green coke is therefore classified as a nontoxic substance [3].

No classification and labeling regarding toxicity, carcinogenicity, flammability, and environmental effects is required. Contents of Ni, V, Na, Ca, and Fe originating from the crude oil residues used as feed are accumulated in green coke. These levels can rises up to approximately 10–500 mg/kg. Small amounts of metals and anions are introduced with the cutting water, which makes up to 5–15% of green coke (cutting water content: Na, Ca, Cl, ). Other heavy metals (Hg, Cd, Pb, Cr, Cu, Co, As) are not traceable (level <1 mg/kg). Hydrocarbons and metals in green coke cannot be elutriated with water (S₄ eluate method). No classification and labeling regarding toxicity, carcinogenicity, flammability, and environmental effects is required.

The following classification is employed for the combustion and explosion behavior (measurement of Deutsche Montan Technologie [DTM], mining test circuit, Dortmund):

Combustion behavior	BZ 3 (local combustion or glowing without spreading)
Glow temperature	300 °C
Ignition temperature	700 °C
Dust explosiveness	Contents >60 g/m3 and with ignition source of >10 000 J

Green coke is normally stored in open piles with sidewalls as protection against the wind. In order to reduce the dust discharge, green coke piles are sprinkled with water.

The potential dust emission is visibly improved by means of dosing antidust additives (polyacrylate types or extract of orange peel) to the sprinkling water.

The general explosive boundary value at work of 6 mg/m³ for fine dust concentrations is to be complied with.